I seem to recall the similar Grunding of my parents back in the mid 50's had a row of 5-6 knobs at bottom center which controlled various audio frequency bands. The visual indications were small beads tied together with red elastic strips behind the glass panel. As the knobs were adjusted the beads moved up or down about 1-2 cm, the elastics stretched and followed to form a mechanical visual display of the resulting frequency resonse.
Replay available now: A handful of emerging network technologies are competing to be the preferred wide-area connection for the Internet of Things. All claim lower costs and power use than cellular but none have wide deployment yet. Listen in as proponents of leading contenders make their case to be the metro or national IoT network of the future. Rick Merritt, EE Times Silicon Valley Bureau Chief, moderators this discussion. Join in and ask his guests questions.